Welded plate heat exchangers are commonly made of flat, parallel plates sandwiched and welded between two cover panels. Two fluids, one relatively hot and the other relatively cold, are passed between alternate plates for heat transfer. The narrow gaps between plates causes the flow paths of both the hot and cold fluids to go down to boundary layer thickness, eliminating the wasted center core of fluid which is pumped through, but not heated or cooled, in standard shell and tube heat exchangers. Plate heat exchangers require less space than shell and tube heat exchangers, and transfer heat at a much higher rate.
The heat exchanger of this invention has among its many features enlarged inlet and outlet openings for the flow paths between plates, thereby substantially reducing the pressure drop and pumping cost. The ends of the plates could be square but are preferably triangular, or V-shaped, lengthening the opening along each edge of the V. This opening is enlarged further by bending the opening-forming edge of one of the two plates for each flow path away from the corresponding edge of the other of those plates and welding it to an adjacent plate.
The heat exchanger of this invention is preferably of all welded construction, is compact, light weight, low in cost, operates at low fluid volume, has a high pressure rating, high performance and high efficiency.
It is an object of this invention to provide a plate heat exchanger having some or all of the above features.
Another object is to provide a plate heat exchanger which is of relatively simple construction, rugged and durable in use, and easy to manufacture and assemble.
Other objects, features and advantages of the invention will become more apparent as the following description proceeds, especially when considered with the accompanying drawings.